Fire door closing system

ABSTRACT

A door closing system for a door supported for movement along a predetermined path. An elongated tension member is length-wise disposed along the path of movement of the door for longitudinal shifting and a fusible anchor is operatively associated with the tension member to anchor it against movement in a first lengthwise direction. A spring mechanism is operatively associated with the anchor member and yieldingly biases the same in the aforementioned first direction. The door includes a follower guidingly engaged with the tension member for movement therealong and the door is shiftable in the aforementioned first direction to a closed position and in the opposite direction to an open position. An abutment is carried by the tension member on the side of the follower opposite to the aforementioned first direction when the door is in the open position and the spring structure biasing the tension member in the first direction is operatively connected thereto at a point spaced in the first direction from the follower of the door when the door is in its closed position, the abutment or enlargement carried by the tension member being abuttingly engagable with the follower of the door upon movement of the tension member in the first direction whenever the door is shifted from its closed position toward its open position in order to transfer the biasing action of the spring structure to the door through the follower so as to bias the door to its closed position upon melting of the fusible anchor.

United States Patent Martindill [54] FIRE DOOR CLOSING SYSTEM [72]Inventor: Herman Y. Martindill, El Doraclo,

Ark.

[73] Assignee: United Specialties, Inc. [22] Filed: April 12, 1971 [2i]Appl. No: 133,116

[52] US. Cl. ..49/4 [51] Int. Cl. ..E05f 15/20 [58] Field of Search..49/l, 3, 4, 5, 6

[56] References Cited UNITED STATES PATENTS 8l4,l92 3/1906 Dentler..49/3 3,039,573 6/1962 Gerhardt ..49/1 3,160,250 12/ l 964 Bridwell..49/1

Primary Examiner-Kenneth Downey Att0rney-Clarence A. OBrien and HarveyB. Jacobson [57] ABSTRACT A door closing system for a door supported formovement along a predetermined path. An elongated ten- 3,683,551 s] Aug.15, 1972 sion member is length wise disposed along the path of movementof the door for longitudinal shifting and a fusible anchor isoperatively associated with the tension member to anchor it againstmovement in a first lengthwise direction. A'spring mechanism isoperatively associated with the anchor member and yieldingly biases thesame in the aforementioned first direction. The door includes a followerguidingly engaged with the tension member for movement therealong andthe door is shiftable in the aforementioned first direction to a closedposition and in the opposite direction to an open position. An abutmentis carried by the tension member on the side of the follower opposite tothe aforementioned first direction when the door is in the open positionand the spring structure biasing the tension member in the firstdirection is operatively connected thereto at a point spaced in thefirst direction from the follower of the door when the door is in itsclosed position, the abutment or enlargement carried by the tensionmember being abuttingly engagable with the follower of the door uponmovement of the tension member in the first direction whenever the dooris shifted from its closed position toward its open position in order totransfer the biasing action of the spring structure to the door throughthe follower so as to bias the door to its closed position upon meltingof the fusible anchor.

2 Claims, 3 Drawing Figures Patented Aug; 15, 1972 Fig./

Herman X Marfindil/ INVENTOR.

FIRE noon CLOSING SYSTEM The fire door closing system of the instantinvention has been designed to overcome some of the objectionableoperating characteristics of presently available fire door closingsystems. Present systems utilizing fusible links or anchors areconstructed in a manner whereby manual operation of the associated firedoor, as occasionally is desired, results in at least partial operationof the automatic fire door closing system. Although proper operation ofsuch automatic fire door closing systems is not always impaired byprevious manual opening and closing of the associated fire door, damageto the fire door closing system can occur, at least in some instances.Further, previous fire door closing systems constructed in a mannernecessitating at least partial operation of the door closing system as aresult of manual shifting of the associated fire door cannot beinspected by regulatory agencies periodically with those regulatoryagencies knowing that the fire door closing system will not in any waybe actuated until actuated by a fire. Therefore, proper inspection andcontrol over present day fire door closing systems. may not be carriedout.

However, the fire door closing system of the instant invention isconstructed in a manner whereby manual opening and closing of theassociated fire door in no way actuates any portion of the fire doorclosing system. In this manner, the system, between periodic checks byregulatory agencies, remains inactive instantly ready for properactuation in the event of a fire.

Further, the fire door closing system of the instant invention is quitesimple in design and relies upon only a tension member, a fusible anchorand a spring mechanism operatively connected to the tension member forfull and complete operation.

.The main object of this invention is to provide a fire door closingsystem which will, in the event of sensing heat associated with a firebeautomatically actuated to close an associated fire door.

Another object of this invention, in accordance with the immediatelypreceding object, is to provide a fire door closing system operativelyassociated with the corresponding fire door in such a manner so that thefire door closing system may be maintained totally inactive duringmanual opening and closing of the fire door.

A still further object of this invention is to provide a fire doorclosing system which may be readily attached to substantially all typesof fire doors.

A final object of this Invention to be specifically enumerated herein isto provide a fire door closing system which will conform to conventionalforms of manufacture, be of simple construction and automatic inoperation so as to provide a device that will be economically feasible,long lasting and relatively trouble free.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIG. 1 is an elevational view of a typical type of sliding fire doorwith the fire door closing system of the instant invention operativelyassociated therewith;

FIG. 2 is an enlarged fragmentary perspective view of the fire doorclosing system in operation sliding the associated fire door toward aclosed position; and

FIG. 3 is an enlarged fragmentary perspective view illustrating thetension member guide pulley of the fire door closing system and itsmounting bracket in operative association with the corresponding firedoor and door mounting track.

Referring now more specifically to the drawings the numeral 10 generallydesignates a wall structure having a door opening 12 formed therein. Anelongated generally horizontal support and guide track 14 is supportedfrom the wall structure 10 and a horizontally shiftable fire door 16 isguidingly supported from the support and guide track 14 by means ofupstanding followers 18 of conventional design supported from the uppermarginal edge portion of the door 16 and guidingly engaged with thesupport and guide track 14.

The support and guide track 14 is substantially horizontal andaccordingly, although the door 16 is supported from the track 14 bymeans of anti-friction followers, the door 16 tends to remain in anyposition disposed along the guide track 14 in which it is placed.

The fire door closing system of the instant invention is referred to ingeneral by the reference numeral 20 and includes a spring loaded windingdrum assembly referred to in general by the reference numeral 22journaled from a mounting bracket 24 anchored to the wall structure 10by means of suitable fasteners 26. The system 20 further includes aZ-shaped mounting bracket 34 including a short upper vertical flange 30secured to the wall structure 10 by means of suitable fasteners 32 and alonger depending lower vertical flange 34 supported from the lower endportion of the upper flange 30 in laterally offset relation relativethereto by means of a connecting horizontal flange 36. The lower end ofthe lower flange 34 has a guide pulley 38 journaled therefrom and theguide pulley 38 is disposed on the side of the door opening 12 remotefrom the side thereof on which the winding drum assembly 22 is disposed.Further, the upper periphery of the guide pulley 38 is disposed along aline tangent to the upper peripheral portion of the winding drumassembly and parallel to the support and guide track 14.

One end of an elongated flexible tension member 40 is anchored to thewinding drum assembly for winding thereon and the other end portion ofthe tension member 40 is trained over the guide pulley 38 and extendsback toward the winding drum assembly 22 and is anchored to the wallstructure 10 adjacent the mounting bracket 24 as at 42. Further, thetension member 40 includes a fusible link 44 and accordingly the fusiblelink 44 and that portion of the tension member 40 extending between thefusible link 44 and the anchor point 42 comprises a fusible anchorconnection for the end of the tension member 40 remote from the windingdrum assembly 22.

The winding drum assembly 22 may be of any conventional spring loadedtype and the spring structure (not shown) thereof yieldingly biases thewinding drum assembly 22 in an counter clockwise direction as viewed inFIGS. 1 and 2 of the drawings. Accordingly, should the fusible link 44be melted, the spring structure of the winding drum assembly 22 willcause counterclockwise rotation of the latter in order to wind thetension member 40 thereon.

The fire door closing system 20 further includes a follow up bracket 46secured to the end of the upper marginal edge portion of the door 16adjacent the winding drum assembly 22 and the follow up bracket 46includes an outstanding flange 48 provided with a horizontal bore 50through which the tensioned tension member is loosely received.

The tension member 40 has a large diameter abutment 52 thereon securedin position in any convenient manner against shifting longitudinally ofthe tension member and the abutment 52 is disposed between the flange 48and the guide pulley 38 when the door 16 is in the open position thereofillustrated in FIG. 1 of the drawings.

In operation, inasmuch as the upper reach of the tension member 40parallels the support and guide track 14 and the tension member 40 isloosely received through the bore 50, the door 16 may be manuallyshifted between the open position thereof illustrated in FIG. 1 of thedrawings and a closed position with the door 16 shifted to the left asviewed in FIG. 1 of the drawings in registry with the door opening 12.During movement of the door 16 between the open and closed positions thefire door closing system 20 is totally inactive in that the edges of theflange 48 defining the bore 50 need not even touch the tension member40. On the other hand, should the fusible link 44 be subjected tosufficient heat to melt the link 44 such as would be the case in theevent of a fire in close proximity to the link 44, as a result of thelink 44 being melted the tension member 40 is released from its anchorto the wall structure and the spring loaded winding drum assembly windsthe tension member 40 thereon with the result that the abutment 52 isshifted toward the winding drum assembly 22 and abuts the face of theflange 48 remote from the winding drum assembly 22 thereby enabling thewinding drum assembly 22 to slide the door 16 along the support andguide track 14 to the left as viewed in FIG. 1 of the drawings until thedoor 16 reaches its closed position. Thus, although the fire doorclosing system is maintained totally inactive during manual opening andclosing of the door 16, it is maintained in a constant ready state toclose the door 16 in the event of a fire. By this operation, the firedoor closing system may be periodically checked by the properauthorities and after being checked the system 20 will be maintained inconstant readiness for automatic operation in the event of a firealthough the door 16 may be manually shifted between the open and closedpositions without operation of any portion of the fire door closingsystem.

Further, in order to prevent the abutment 52 from impacting too sharplywith the flange 48, a coiled compression spring 56 is loosely disposedon the tension member 40 intermediate the flange 48 and the abutment 52.Accordingly, should the door 16 be disposed in a partially closedposition when the fusible link 44 melts and releases the tension member40 for rapid winding on the spring loaded winding drum assembly 22,impact of the abutment member with the flange 48 will be cushioned bythe spring 56.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

1. In combination with a building structure having a doorway therein anda fire door supported adjacent one side of said doorway for generalhorizontal shifting to a closed position in registry with said doorway,an elongated tension member generally paralleling the path of movementof said door between its open and closed positions and extending betweenthe opposite sides of said doorway, said tension member being supportedfor longitudinal shifting, force means connected to said tension memberon the other side of said doorway yieldingly biasing said tension memberin a lengthwise direction to said other side of said doorway from saidone side thereof, a follower supported from said door and movable alongsaid tension member in close proximity thereto during shifting of saiddoor between said open and closed positions, an abutment carried by saidtension member on the side of said follower remote from said other sideof said doorway and engagable with said follower upon shifting of saidtension member toward said other side of said doorway to thus shift saiddoor from the open position thereof to the closed position thereof, andreleasable anchor means attached to said tension member for preventinglongitudinal shifting thereof toward said other side of said doorwayunder the biasing action of said force means, said releasable anchormeans including a fusible portion thereof which will melt, and therebyrelease said elongated tension member for movement under the biasing ofsaid force means, in response to being subjected to sufficient heat,said tension member comprising an elongated flexible member, said forcemeans comprising a spring bias winding drum supported at said one sideof said doorway and to which the adjacent end portion of said tensionmember is attached for winding thereon, a guide pulley supported fromthe other side of said doorway and about which the other end portion ofsaid tension member is passed said releasable anchor means serving toanchor the end portion of said tension member passed about said guidepulley to said one side of said doorway, said follower comprising anoutstanding flange carried by said door having an opening formedtherethrough through which the reach of said tension member extendingfrom said winding drum to said guide pulley is loosely received, saidabutment being mounted on said tension member between said flange andsaid guide pulley.

2. The combination of claim 1 including a coiled compression springloosely disposed on said tension member intermediate said follower andabutment means.

2. The combination of claim 1 including a coiled compression springloosely disposed on said tension member intermediate said follower andabutment means.